blow-holen1 vent for air, smoke, etc in a tunnel （隧道的）通风口.2 hole in the ice through which seals, etc breathe （海豹等用以呼吸的）冰窟窿.3 whale's nostril situated at the back of its skull （鲸鱼的）鼻孔.
牛津英汉双解词典